Yeah, the engines help a lot with rendering, physics, and scene/level building/making custom tooling, and a bunch of other things. They are honestly amazing tools.

AAA and indies now use the same engines for the most part

In game dev however, there's a lot fewer reliable open source tools around. You have a game engine, a small number of great plugins, and a lot of dodgy stuff. You have to/get to make a lot of things yourself.

The scope and complexity of indie games, even allowing for this, is still increasing staggeringly.

...and don't get me started on unreal engine physics and pathfinding issues, or rendering bugs in unity